Printheads may be used to eject ink or another fluid onto a receiving medium such as paper. Applications include, but are not limited to printers, graphic plotters, copiers and facsimile machines. Such apparatus use an ink jet printhead to shoot ink or another material onto a medium, such as paper, to form a desired image. More generally a print head is a precision dispensing device that precisely dispenses fluids such as ink, wax, polymers or other fluids. While printing to form an image on a receiving medium is one application, printheads are not limited to this and may be used for other purposes, such as manufacturing, digital titration, delivery of pharmaceuticals or 3D printing for instance.
Fluid may be delivered via a fluid slot of the print head to an ejection chamber beneath a nozzle. Fluid may be ejected from the ejection chamber by heating or by a piezo-electric pressure wave etc. Various factors affect the performance of the printhead, including the temperature of the fluid and surrounding printhead. Some printheads include a temperature sensing resistor which is used to detect a temperature of the printhead.